Facies patterns and subsidence history of the Jumilla-Cieza region (southeastern Spain)

A detailed analysis of the facies patterns and subsidence history since the Late Cretaceous (100 Ma) of the Jumilla-Cieza region in southeastern Spain, has implications for the debate on the mechanisms causing third-order changes in sea-level. The local subsidence history shows periods characterized by specific trends in tectonic subsidence, each with a typical concomitant facies pattern. The successive periods are considered to illustrate the transition of the southern Iberian plate boundary from a passive margin (108-40 Ma), through an extensional phase (40-20 Ma) to a thrust-and-fold belt (20 Ma to Recent). Timing and changes in relative sea level derived from the sedimentary record, closely match with the regional tectonic events. The order of magnitude of these sea-level changes exceed those predicted by the "global" curve. Therefore, we suggest that, in the studied area, third-order sea-level fluctuations are of relatively minor magnitude and only enhance the effect of tectonic-induced vertical movements.